You can get the Trials Trophy way before completing all of the levels in the game. All you need to do is complete the first seven events. Doing so will unlock the trophy for you and unlock the final event in the game.

In Trials Fusion, there are three challenges on three separate tracks that are all called "Full Throttle". What they mean is to complete the track without ever releasing acceleration or using the brake. Remember that you can accelerate by pulling in the right trigger.

These are the three levels that you need to complete the "Full Throttle" challenge on:

This is how to get the achievement/trophy called Leavin' a Fine Lookin' Fossil.

The description for the achievement/trophy says as follows:

Hold a "Proud Hero" pose to your demise, dressed in an Excavator outfit

To do this, you first have to go to the Garage and purchase three pieces of "Excavator" clothing and make sure it is equipped to your rider.

Then pick one of the FMX tracks. To perform the "Proud Hero" pose, make sure your bike is perfectly level after ramping into the air. Then pull down on the right analog stick and hold it in that position. If done properly, your rider will then perform the "Proud Hero". Keep this pose until your rider crashes into the ground or something else and the achievement/trophy will unlock.